Varrius

iTrader: (1)

Autometer Carbon.

Varrius

iTrader: (1)

As for the HP TXS Boost Controller, they re-did the entire design. it used to be an alan wrench adjusted unit with a little bit different internal-workings. Now it's adjusted by simply turning the top negative or positive, it's a LOT better. They just recently updated the design.


" High Perfomance Boost Controller (BC-HPBC)
Utilizing a uniquely engineered ball/spring mechanism combine with an adjustable bleed valve, the BC-HPBC allows you to spool your turbo to full boost up to hundreds of RPM faster than stock! The adjustable bleed mechanism lets you minimize the massive boost "spike" that can occur with poorly designed ball/spring manual boost controllers. "

Varrius

iTrader: (1)

Also, the TXS MBC does suck. That's not the what I have, nor the other gentleman had. We have the HP model, with an entirely different system.

Rnm

iTrader: (4)

I have a Forge UNOS and I still taper that much as well, its normal.

boostingevo8

Me too....hit 22psi but taper to 20/19 psi around redline. I have 269 cams and heard it's a big issues with the evo 8 especially running cams.

RenoEvo

iTrader: (43)

Warr I dont see the issue with the boost if he was safely tuned for that pressure. I've seen several IX's hit 24-25psi on 91 oct. let alone 93

Warrtalon

iTrader: (6)

He wasn't tuned in 4th and 5th gear, I'm sure. I'm also sure you've seen people hit that on 91, but that doesn't mean it's a good idea.

RenoEvo

iTrader: (43)

Oh god here we again with your generalizations I'm not even going to argue with you anymore on what's safe and whats not, as its a losing battle. Bottomline, your comment was misleading and plain wrong. Many evo IXs are SAFELY tuned with high boost and less timing, come on you know this!

Varrius

iTrader: (1)

My car was tuned to spike 24psi in third gear on a Mustang dyno by Jestr Tuning. You can speak to him if you want to call him a "liar."

RenoEvo

iTrader: (43)

Jestr knows whats up so I'm sure you're car got a powerful and safe tune, so don't worry about Warrs ignorant comment. As long as you have a safe tune and you monitor your car, peak psi isn't a big issue because every car is different. To answer the original question your boost taper is perfectly normal for a stock ecu/turbo IX!

AZ EVO IX MR

iTrader: (10)

on 104 sunco i hit 32 psi and taper to 21 in third

machron1

iTrader: (1)

What I used to do was close the bleeder valve almost all the way and set the ball/spring for roughly the boost I wanted just after the spike. Then I would use the small bleeder valve to dial out the spike. This would then drop the overall boost slightly, so I would very slightly increase the ball/spring pressure. This sometimes introduced another slight spike, so again I would tune it out with the bleeder. I had great luck with my old style even with the alan-key adjustment screws. Maybe people just don't have the patience to tune both valves? I dont' know why you would need to ditch the thing because of the bleeder valve since you can just close it all the way anyway. If I was going to stay with a MBC that's definitely the one I would get again.

Jeff_Jeske

iTrader: (66)

I think the bottom line is that boost taper is normal. There are ways to try to make the turbo hold higher boost but that doesn't mean its better for performance. The turbo can only flow X amount of air. Running it at a higher boost level will probably do more harm than good. Spiking to 24 is acceptable if tuned for it but I agree with Warr that running 25PSI in taller higher load gears is probably not a good thing. I would be willing to bet he is getting knock and timing pull. I would be interested in a log of timing during a high gear pull.

machron1

iTrader: (1)

Yes taper is normal. I think you should strive to avoid spiking though. I will gladly give up some ramp-up time for a smooth boost curve.

Varrius

iTrader: (1)

Jestr said there was no Knock what-so-ever during the tune.